1971 Hemi Cuda - Shades Of Gray

Outrageousness. If you build your cars for fun, that's the one thing that always garners attention. Crazy paint, blower motors, or 11-second station wagons gather the gawkers and stick 'em like flypaper. Plymouth's '71 'Cuda was a prime example of crazy right off the assembly line, so it takes some doing to take it over the top.

Then again, outrageousness only goes so far. What's under the surface makes or breaks you in the sphere of public opinion. Conversely, subtlety is a great way to stand out from the crowd (hot librarians in glasses, anybody?). The idea that something looks sedate but proves potent is heady stuff. Everybody walks by once and says, "Oh, that's nice." The shock only registers when they go deeper to realize just how unique, complex, or efficient the package is. This 'Cuda, floating in a small but very visible sea of million-dollar drop-tops, high-quality clones, and hot factory paint codes, chose to make its big statement with a little less lipstick.

Panther Pink, Sassy Grass Green, and Moulin Rouge were all on the Plymouth paint list in 1971, but as owner Justin Helms began to decide how the end package should look, he chose a sedate DuPont Silver with Graphite accents and one narrow Hemi Orange pinstripe. Not eye-popping, to be sure, but well executed and definitely not run-of-the-mill on this body style.

Justin will be the first to admit he has a back door regarding horsepower. He and his brother work full time for Joey Arrington Racing Engines (officially known as Arrington Manufacturing, Inc., or AMI) in Martinsville, Virginia, doing research and development on Dodge's NASCAR Craftsman Truck motors. Familiarity with late-model engine power left both the car's factory 340 and the old-school 7.0L elephant at the door. This Hemi is a modern 6.1 version, stroked out to make a legendary 426 inches (7.0 liters, as denoted on the scoop).

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And though those cool custom billet CNC valve covers are simple dress-ups that bolt right on top of the factory ignition-support versions, what's inside is high tech. After boring and prepping the block for the bigger K1 long arm and rods, 10.25:1 compression pistons by Mahle were added, and a custom roller cam ended up in the middle. Most of the 6.1s OEM valvetrain was still retained.

The CNC machinery at AMI also carved the factory aluminum heads and a custom intake supports a pair of FAST electronic throttle-bodies. Set at the same height as the original Hemi, a standard factory Shaker scoop unit was adapted to this layout with a custom baseplate, with Pro Fab headers and a full 3-inch exhaust at the other end of the combustion cycle. In the end, 585 hp and 560 torque numbers were on the dyno sheet. Behind this went a Keisler five-speed and a 4.10:1-ringed Dana from DTS.

The old suspension received attention as well. AlterKation creates tubular replacements for the factory's heavy K-frame support under the engine; since fresh motor mounts and locations would have had to be custom-built anyhow, this was a no-brainer (plus it improves handling). Out back, the leaf packs went away for an Air Ride layout and traction links. Brakes use big 12.25-inch Wilwood vented rotors, functioning and visible behind large custom-made 18-inch black billet rims.

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Meanwhile, the standard factory interior received upgrades like a custom dash with TPI gauges that Joe helped build and a Legendary custom leather interior. We aren't going to sit here and say that anybody can do this in his backyard in an afternoon, or convince you that you can build a car like this on a beer budget. Still, with the right possibilities available, the choice to build a car in the gray areas rather than the more common visual extremes can hold their own.

Body: It has mild changes for big tires, and a fresh trans tunnel, but otherwise the factory had already pushed the envelope on this body design.

Engine: The displacement is 426 inches, but that's in a late-model 6.1 core. Since this was built at Arrington Manufacturing, prep and meticulous assembly are a given. A K1 stroker crank and rods, 10.25:1 Mahle pistons, and a Custom Cam Co. (one of AMI's subdivisions) roller cam are in here for a true 7.0L package.

Goodies: The top of the engine has a pair of FAST throttle-bodies on a custom intake, covered by a Shaker. AMI did the custom CNC work, including the engine covers over the valve covers. The oil pan gives proper clearance for the front suspension; that came from AMI's metal shop as well.

Heads: More CNC work went into these aluminum units. In the end, the package was good for 585 ponies and 560 lb-ft of torque on the dyno.

Ignition: The sparker uses FAST pieces, set up by Arrington.

Interior: The interior has leather seat covers from Legendary, a custom dash with TPI gauges, and an Impy's steering wheel. A new-gen Pistol Grip comes through the rebuilt trans tunnel.

Paint: The hue is DuPont Silver and Graphite, with a single pinstripe in Hemi Orange, of course....

Rearend: It's a Dana 60, set up by DTS, with a 4.10:1 SureGrip limited slip.

Suspension: It has Air Ride components in the rear, adjustable shocks, and monster 12.25-inch vented rotors at all four corners thanks to Wilwood. An AlterKation K-frame replaces the heavy OEM version and helps facilitate the engine swap.

Transmission: Five forwards and one reverse, courtesy of Keisler

Wheels/Tires: These are custom billets measuring out at a very large 18 inches (8-inch-wide front and 10-inch- wide rear). Soft, low-profile Nitto rubber makes it stick. That is 235 and 285, respectively.